Apparatus for lifting and turning a bed patient



April 21, 1970 F. F. LANG 3,506,985

APPARATUS FOR LIFTING AND TURNING A BED PATIENT Filed July 15, 1968 6Sheets-Sheet 1 INVENTOR FREDERIC F. LANG ATTORNEY F. F. LANG April 21,1970 6 Sheets-Sheet 2 Filed July 15, 1968 ATTORNEY I April 21, 197 F. F.LANG 3,506,985

APPARATUS FOR LIFT'ING AND TURNING A BED PATIENT Filed July 15, 1968 6Sheets-Sheet 3 INVENTOR FREDERIC F. LANG ATTORNEY April 21, 1970 F. F.LANG 3,506,985

APPARATUS FOR LIFTING AND TURNING A BED PATIENT Filed July 15, 1968 6Sheets-Sheet 4;

I INVENTOR '9' FREDERICFLANG ATTORNEY April 21, 1970 F. F. LANG3,506,985

APPARATUS FOR LIFTING AND TURNING A BED PATIENT Filed July 15, 1968 Y 6Sheets-Sheet 5 INVENTOR FREDERIC F. LANG ATTORNEY April 21, 1970 F, LANG3,506,985

APPARATUS FOR LIFTING AND TURNING A BED PATIENT Filed July 15, 1968 6Sheets-Sheet 6 INVENTOR FREDERIC E LANG ATTORNEY United States Patent3,506,985 APPARATUS FOR LIFTING AND TURNING A BED PATIENT Frederic F.Lang, Daytona Beach, Fla. 32016 Filed July 15, 1968, Ser. No. 744,774Int. Cl. A61g 7/10 US. Cl. 81 8 Claims ABSTRACT OF THE DISCLOSURE Aportable apparatus capable of being readily positioned over and around aconventional bed and utilizing reversible electric motors forselectively raising or lowering the ends of a flexible sling which ispositioned under the body of a patient occupying the bed, for gentlyraising the patient off of the bed and for turning the patient over ineither direction.

BACKGROUND OF THE INVENTION This invention relates to the art of devicesto effect the lifting and turning of bed ridden patients who arephysically incapacitated for accomplishing such movements themselves.

The prior art discloses mechanical devices for use in lifting andturning bed patients to eliminate the necessity of such operation beingaccomplished entirely manually by the attendants. However, in the priorart devices, one or two attendants are required to operate the apparatusto effect the lifting and turning movement of the patient.

SUMMARY It is a primary object of the present invention to provide anapparatus which may be operated or controlled solely by a bed-riddenpatient to effect a lifting of the hips and shoulders from the bed andthereafter a turning of the body over in either direction.

Another object of the invention is to provide such an apparatus whereinthe manipulation of only two fingers of either hand of the patient isrequired to control the operation of the device and to enable themovements of the body to be accomplished gently and at different speeds,in accordance with the will of the user.

A further object of the invention is to provide an apparatus which isportable to enable it to be moved readily from one bed to another andutilized in conjunction with a conventional bed, such as a hospital bed,without any modification of the bed or without any direct attachmentthereto.

A further object of the invention is to provide an apparatus including aflexible sling in which the body of the patient is supported while beingraised, lowered or turned, and which is formed in part of a conventionaldrawsheet.

A further object of the invention is to provide an apparatus havingmeans to automatically effect stopping of the drive means to which thesling ends are connected as such sling ends approach the extremities oftheir movements in either direction.

Still another object of the invention is to provide an apparatus havinga novel control means the manipulation of which may be determined by thesense of touch.

Various other objects and advantages of the invention will hereinafterbecome more fully apparent from the following description of thedrawings, illustrating a presently preferred embodiment thereof, andwherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view showingthe lifting and turning apparatus in an operative position;

FIGURE 2 is an enlarged fragmentary vertical sectional view of a portionof the apparatus;

FIGURE 3 is an enlarged fragmentary perspective view, partly brokenaway, of another part of the apparatus;

FIGURE 4 is an enlarged fragmentary perspective view, partly in sectionand partly broken away, illustrating one of the motorized units of theapparatus;

FIGURE 5 is a longitudinal sectional view, on a reduced scale, of aportion of the structure shown in FIG- URE 4 and taken substantiallyalong a plane as indicated by the line 5-5 of FIGURE 6;

FIGURE 6 is a cross sectional view of the structure seen in FIGURE 5,taken substantially along a plane as indicated by the line 66 of FIGURE5;

FIGURE 7 is a perspective view, partly broken away and partly insection, illustrating the control unit of the apparatus;

FIGURE 8 is a side elevational view, partly in section, showing one ofthe electric motors of the apparatus and the gear train thereof;

FIGURE 9 is an enlarged perspective view of a part of the bodysupporting sling;

FIGURE 10 is a side elevational view, partly in section, of one endportion of the structure as seen in FIG- URE 9;

FIGURE. 11 is a cross sectional view of another part of the structure ofFIGURE 9;

FIGURE 12 is a side elevational view of one of the elements of FIGURE11;

FIGURE 13 is a diagrammatic view in perspective of a portion of thecontrol unit of FIGURE 7;

FIGURES 14 and 15 are views similar to FIGURE 13 but illustrating twoalternate positions of certain of the parts, and

FIGURE 16 is a diagrammatic view illustrating the electric circuits ofthe apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more specifically tothe drawings, the lifting and turning apparatus in its entirety andcomprising the invention, is illustrated in FIGURE 1 and designatedgenerally 20. The apparatus 20 includes an arch-shaped supportingstructure, designated generally 21, which is adapted to straddle aconventional single bed 22, and which includes corresponding sidemembers 23 each having an elongated horizontal bar or base v24 which issupported for movement on a pair of caster wheels 25. A lower tubularpost section 26 is fixed to and rises from the bar 24 and the lower endof an upper post section 27 telescopes into the upper end of the postsection 26, as best seen in FIGURE 2. One side of the bar '27 haslongitudinally spaced outwardly opening sockets 28 to selectivelyreceive a pin 29 which fits slida'bly in an opening 30 on-one side ofthe post section 26. The pin 29 is urged inwardly toward post section 26by a leaf spring 31, to the inner side of which it is secured, remotefrom fastenings 32 by which an end of the leaf spring is secured to thepost section 26. It will be apparent that the other free end of the leafspring can be sprung outwardly for disengaging the pin 29 from socket 28for extending or retracting the post section 27 relative to the postsection 26, and that both of the side members 23 will be adjusteduniformly.

The upper end of each post section 27 is secured in any conventionalmanner to a depending end 33 of an angular joint 34 having a bore 35disposed at a right angle to the post portions 26 and 27. A rigid tube36, constituting the top portion of the supporting structure 21, issupported at its ends in the bores 35. Each joint 34 has a slot 37extending downwardly from its bore 35. Headed screws 38 span the slot 37and threadedly engage in sockets 39 of the joint part 33 and may betightened for restricting the slot 37 and bore 35 for clamping the endof the tube 36 in said core 35.

As seen in FIGURES 1 and 4, two lateral motion recirculating ballbushings 40 are mounted to slide and turn on the tube 36. Each bushing40 is fixed to and disposed crosswise of an intermediate portion of ahanger 41 which is suspended thereby and which has depending ends 42containing aligned bushings 43 in which are journaled the ends of a pin44 which extends through a sleeve 45 of a balance plate 46, as seen inFIGURE 4. The pin 44 and sleeve 45 are disposed beneath and crosswise ofthe tube 36.

The right hand plate 46 supports a right hand motorized unit 47(FIGURE 1) and the other left hand plate 46 supports a left handmotorized unit 48 (FIGURES 1 and 4). The unit 47 includes a series woundelectric motor 49 and unit 48 includes a corresponding electric motor50. Each motor 49 and 50 has a gear casing 51 preferably formed integralwith and projecting from an end of the motor housing and which isconnected to and suspended beneath one of the balance plates 46 by screwfastenings 52.

FIGURE 8 shows the motor 50 and its casing 51 inverted with respect toits position of FIGURE 4. As seen in FIGURE 8, a pinion 53 on thearmature shaft of the motor 50 meshes with and drives a gear 54 which isjournaled on a stub shaft 55, one end of which is supported in a socket56 of the casing 51. Gear 54 has an integral pinion 57 which meshes witha gear 58 which is secured to a worm shaft 59 by a key 60 and set screw61. One end of the shaft 59 is journaled in a socket 62. Thrust on saidshaft end is taken up by a ball 63 and thrust plate 64. The other end ofthe shaft 59 is journaled in a socket 65 of the casing 51 and bearsagainst a ball 66 which is held in contact therewith by a screw 67,threaded into the casing 51, and by which end play is adjusted. A locknut 68 retains the screw 67 in adjusted positions. A worm 69 on theshaft 59 meshes with a worm gear 70 which is fastened immovably to ashaft 71 by setscrews 72. The parts 53 to 67, 69 and 70 are contained inthe casing 51.

The arrangement of the pin 44 and hanger 41, FIGURE 4, provides gimbalsaction between the tube 36- and the electric motor of either the unit 47or the unit 48. Fastened to the housing of the gear motor of each unit47 and 48 by screw fastenings 73, FIGURE 4, are spaced apartsubstantially parallel plates 74 and 75 having aligned bearings 76 inwhich are journaled the ends of the motor output shaft 71. Acountershaft 77 is journaled in bearings 78 of the plates 74 and 75,below the shaft 71. The shaft 77 is driven from the shaft 71 by asprocket wheel and chain drive 184, located adjacent the side plate 75,for driving the shaft 77 in either direction from the reversibly drivenmotor shaft 71.

A drum 79 is secured to the intermediate portion of the countershaft 77.The part of the circumference of the drum 79 "which is located adjacentto the motor, is in a direct perpendicular line with the pin 44 and tube36. In addition, the balancing point of the electric motor of the units47 or 48, and the parts connected thereto, is

located at the intersection of the tube 36 and pin 44, permitting theentire motorized unit to be suspended in a symetrically balancedposition from the tube 36.

As seen in FIGURE 4, two electrical conductor rings 80 and 81 aremounted on the end of the drum 79, located nearest the plate 74, inelectrically insulated relation to one another and are engaged byconductor brushes 82 and 83, respectively, which are supported by abracket 84 which is secured to plate 74, below and adjacent the shaft 77A bracket 85 is secured to and extends inwardly from the plate 74,beneath the bracket 84, and has a bottom portion providing a support foranelectrical contact'86' which extends upwardly therefrom. A bar 87 ispivotally supported on the upper part of the bracket by a pin 88 forvertical swinging movement and supports a downwardly extendingelectrical contact 89 which is held in engagment with the contact 86' bya leaf spring 90 which bears downwardly on the bar 87.

The bar 87 has a bifurcated outer end 91 through which'extends anon-elastic flexible tape 92 the upper end of which is fastened to thedrum 79, as will hereinafter be described. The tape 92 passes between apair of rollers 93 which are journaled on shafts 94 which are fastenedto and project from the plate 74, below the bracket 85. A roller 95 isjournaled on a shaft, not shown, which projects from the bracket 84 andengages the tape 92 above the bifurcation 91 and cooperates with therollers 93 to maintain the tape 92 positioned for travel between thefurcations of the bifurcated portion 91 without contacting saidfurcations.

Referring to FIGURES 5 and 6, one end of the tape 92 is anchored in arecess 96 of the hub of the drum 79 by a clamping member 97 which issecured to the hub by screw fastenings 98. The member 97 is shaped toprovide a smooth uninterrupted continuation of the periphery of the hub.The drum hub has a second outwardly opening recess 99 in the bottom ofwhich is located an electrical contact 100 which is electricallyconnected to the ring 80, and above which is disposed an electricalcontact 101"'which is supported by a bar 102 which is pivoted at 103 andwhich is urged to a wing upwardly by a spring 104 which electricallyconnects the contact 101' to the ring 81. When the tape 92 is wound onthe drum 79 the pressure thereof causes the bar 102 to swing inwardly tomove the contact 101' into engagement with the contact 100'. When thetape is almost completely unwound from the drum 79, it will move out ofengagment with the bar 102 allowing the spring 104 to displace said baroutwardly to disengage the contact 101' from the contact 100'.

It will be understood that the left hand mechanized unit 47 will includeall of the parts previously described and illustrated in FIGURE 4. Thelower ends of the tapes 92 are connected to bridles 105, as seen inFIGURE 1. Referring to FIGURES 9 to 12, each bridle 105 in cludes a bar106 having an intermediate portion provided with an opening 107 whichextends vertically therethrough for receiving the other end of one ofthe tapes 92 which is passed downwardly therethrough and looped around awedge 108, as seen in FIGURE 11, which clamps the lower end of the tape92 in the flared lower end 109 of the opening 107. The wedge 108 hasnotched side edges 110 to be manually engaged for extracting the wedgefrom the flared portion 109, and the sides of the wedge and the portion109 are preferably knurled, as seen at 111, to provide a betterengagement with the tape.

The bar 106 has a depending end portion 112 in which is ournaled one endof a rod 113 which is attached thereto by a nut 114. The rod 113 extendsaxially through and is secured to a roller 115 which is disposed forrotation between the end piece 112and a hollow casing 116 whichconstitutes the other end piece of the bar 106, and in an inner wall ofwhich the other end of the rod 113 is journaled.'A ratchet wheel 117 isfixed to the last mentioned end of the rod 113 and is engaged by thenose of a pawl 118 which is pivoted at 119, intermediate of its ends,'in the casing 116 and has an opposite end forming a handle 120 whichprojects outwardly through a slot 121 in the casing 116. A spring122,'contained in the casing 116, urges the nose of the pawl intoengagement with the teeth of the ratchet wheel117, which teeth areinclined so that the roller 115, rod 113 and pawl 118 may be rotated inone direction, clockwise as seen in FIGURE 9, but are retained againstrotation in the opposite direction except by manually manipulating thehandle 120 for disengaging the nose of the pawl 118 from the ratchetwheel teeth.

The roller 115 is formed of or coated with a material having a highcoefficient of friction, such as rubber, and has grooves 123 extendinglongitudinally thereof for additionally affording a gripping action onthe end of a drawsheet 124, FIGURE 1, which is wound thereon. The otherend of the drawsheet 124 is wound on the roller 115 of the bridle of theother unit 47.

The ends of the drawsheets are passed over the tops of the rollers 115from the inside outward, which is in the direction that the ratches willallow the rollers to be turned without manually releasing the pawls 118.After several layers of the drawsheet have been wound around eachroller, the natural gripping action will prevent slippage of thedrawsheet ends from the rollers. This application of the drawsheet endsto the rollers provides a smooth surface between the wound ends of thedrawsheet. Hooks 125, FIGURE 1, are provided on the uprights 27 forsupporting the bridles 105 when the apparatus 20 is not in use.

An electrical control unit 126 is electrically connected to a motor 50by a recoila'ble electric cable 127, FIGURE 1, and the motor 49 iselectrically connected to the motor 50 by a second recoilable cable 127'which extends through the tube 36. A conventional electric cord 128extends from the motor 50 and has-a standard three prong plug 129 forconnection to any 110 volt, 60 cycle alternating current outlet.

As best seen in FIGURE 7, the control unit 126 includes a flat baseplate 130 having a hood 131 secured over one end thereof to form ahousing containing an open top receptacle 132 of electrical insulatingmaterial in which is mounted a wall 134. Identical open top housings 133are mounted in the receptacle 132 on opposite sides of the wall 134.Each housing 133 is supported by a pair of compression springs 135 and135' which are located adjacent the ends thereof and rest on the bottomof the receptacle 132. A button 136 fits telescopically into one of thehousings 133 and a corresponding button 137 fits telescopically into theother housing 133. The buttons 136 and 137 project upwardly from thehousings 133 and are each yieldably supported on and urged upwardly by acompression spring 138.

FIGURES 13, 14 and 15 show the wall 134, one of the housings 133 and thebutton 137, but with the housing and button displaced away from the Wallrelative to its normal position of FIGURE 7, for the sake of clarity.Each housing 133 is pivotally mounted for rocking movement on a shaft139 which projects from the wall 134. Each side of the wall 134 has anupwardly opening recess 140 including end portions 141 and 142 whichextend downwardly below its intermediate portion to provide an upwardlyfacing shoulder 143 between said end portions. An index pin 144 projectslaterally from each button 136 and 137, as seen in FIGURE 7, and has afree end engaging the recess 140 which faces said button.

The button 137 is connected to the motor 50 by electrical conductors ofthe cable 127 and the button 136 is connected to the motor 49 by otherelectrical conductors of the cable 127 and by conductors of the cable127'.

FIGURE 13 illustrates a neutral position of the button 137 and itshousing 133 with no electrical connections being made. In this position,the button 137 is in a raised position and its housing 133 is in a levelposition with the index pin 144 resting on the shoulder 143 andpreventing any downward movement of the button 137.

In FIGURE 14, the finger button 137 and its housing 137 are shown tiltedto the left by the housing 133 rocking on the shaft 139 thereof anddepressing the spring 135. This moves the index pin 144 into alignmentwith the recess portion 141 to allow the button 137 to be depressed andmoving its contact 145 into engagement with a contact 146' which issupported by a spring 147.

In FIGURE 15, the housing 133 and its button 137 are shown tilted aboutthe shaft 139 in the opposite direction, or-to the right, for depressingthe spring 135 and to position the pin 144 in alignment with therecessed portion 142 so that the button 137 can be depresed as the pinmoves into said recessed portion.

In the diagrammatic view, FIGURE 16, the right hand button 136 is shownin a position corresponding to the position of the button 137 in FIGURE15. The downward displacement of the button 136 in this positionoperates potentiometer 148 causing electric current to fiow through thecircuit to the motor 49. When the finger button 137 is tilted to theleft and depressed, as in FIGURE 14, and as seen in the lower part ofFIGURE 16, it operates the other potentiometer 148', associatedtherewith, and also closes the contacts and 146' which excites the relaycoil 149' of the electric circuit of the button 137.

When the button 136 is in its position of FIGURE 16, a conductor 150from the prong 151 of the plug 129 connects with contact point 152 ofrelay 149 in the circuit of the button 136, which contact 152 isnormally in engagement with contact 153 which, in turn, is connected tocontact 89 which normally engages contact 86. Before reaching thecontact 152, the current flows through the conductor 150 to theconductor 150a of the circuit of the button 136. Speed is controlled bythe amount that the button 136 is depressed in the housing 133 causingcontact 154 to move across the potentiometer 148, thereby upsetting thepotential balance between two silicone rectifiers placed back-to-back,155 and tryac 156. This provides the proper control for the series woundmotor 49 by changing the crest of the waves in the 60 cycle alternatingcurrent supply for maintaining a high torque at low speed. The sameapplies to the control of the speed of the motor 50. The current flowsfrom the conductor 150 to the conductor 150" through a condensor 157',potentiometer 148' and tryac 156'.

A conductor 158 connects the contacts 153 and 89 and a conductor 159connects the contact 86 to a terminal 160 from which the current flowsthrough the armature winding 161 of the motor 49 to the terminal 162.From the terminal 162, current flows through conductor 163 to a contact164 which normally engages a contact 165 from which a conductor 166leads to a terminal 167, from which the current flows through a fieldwinding 168 of the motor 49 to the terminal 169, from which a conductor170 leads back to the prong 171 of the cap 129. The third prong 172 isgrounded to provide a ground connection for the chassis of the apparatus20 to the grounding system of the electric supply. With the button 136in its position of FIGURE 16, the motor 49 is driven in a direction forrevolving the drum 79 of the unit 47 in a clockwise direction forwinding the tape 92 thereon, at a speed determined by the extent thatsaid button 136 is depressed. The tape 92 near its lower end carries arivet 173 which is shown in FIGURE 4 and which protrudes from both sidesof said tape. The rollers 93 have restricted portions 174 through whichthe rivet 173 can pass. When the rivet 173 engages the bifurcated part91, it rocks the bar 87 upwardly about its pivot 88 against the actionof the spring 90 for disengaging the contact 89 from the contact 86 tointerrupt the electric circuit of the button 136 and deenergize themotor 49, to prevent further clockwise rotation of the drum 79.

From the foregoing, it will be apparent that both buttons 136 and 137could be disposed in the position of the button 136 in FIGURE 16 forwinding both tapes 92 on the two drums 79 for drawing the sheet 124upwardly for gently lifting a patient resting thereon.

The button 137 is shown in FIGURE 16 in its position of FIGURE 14, sothat current is flowing through the parts 148, 154', 155, 156' and 157of the circuit of the button 137 from the branch conductor 150 of saidcircuit to the conductor 150k thereof. In addition, current is shuntedto relay coil 149 of the circuit of the button 137 by a closing of thecontacts 145 and 146' which occurs when the button 137 is tilted as seenin FIGURE 14. The magnetic field of said coil 149' causes point 152' todisengage point 153' and to move into engagement with point 173.Likewise, the point 165' moves out of engagement with point 16-4 andinto engagement with point 175. Current flows from contact 173 through aconductor 174 and conductor 163 to terminal 162, through the armaturewinding 161 of motor 50 to terminal 160', through conductor 159' tocontacts 175 and 165', through conductor 166 to terminal 167, thenthrough the field winding 168' of the motor 50 to terminal 169 and backto the prong 171 through the conductor 17 for causing the motor 50' todrive the drum 79 of the unit 48 counterclockwise to unwind the tape 92therefrom.

The current which excites the relay coil 149' of the button 137 passesthrough a conductor 176 to the contact 101' which is in engagement withthe contact 100' and through a conductor 177 to the conductor 170'. Thering 81 and brush 8-3 constitute parts of the conductor 176 and the ring80 and brush 82 constitute parts of the conductor 177. Thus, when thetape 92 is almost completely unwound from the drum 79 and disengages thebar 102, the spring 104 will move the contact 101 out of engagement withthe contact 100 to break the electric circuit to the motor 50.

It will thus be seen that the buttons 136 and 137 may be manipulated forcausing both motors 49 and'50 to turn either clockwise orcounterclockwise for winding the tapes 92 thereon or for unwinding thetapes therefrom, respectively, for either raising or lowering,respectively, the drawsheet 124 and the patient support-ed thereon. Itwill also be apparent that one button may be positioned for causing themotor thereof to turn clockwise while the other motor is turningcounterclockwise for raising one endof the drawsheet while the other endthereof is being lowered for turning the patient over while being heldin a raised position above the bed 22.

It will be readily apparent that the buttons 136 and 137 may be operatedby two fingers of either hand of the patient and by the sense of feelalone, if necessary, due to the raised dots 17-8 and 178' on buttons 136and 137, respectively. The other end of the plate 130' provides a restfor the wrist while the unit 126 is being operated. Said other end hasan opening 179 to be suspended from a hook 180 on one of the uprights 27when the apparatus 20 is not in use.

As seen in FIGURE 7, the buttons 136 and 137 have extensions 181 whichengage under the ends of openings 182 of the hood 131, through whichsaid buttons project, for maintaining said openings closed when thebuttons are rocked to the right or left. The circuits of the buttons areprotected by fuses 183.

Various modifications and changes are contemplated and may be resortedto without departing from the function or scope of the invention.

I claim as my invention:

1. An apparatus for lifting and turning a bed patient comprising asupporting structure, two motorized units suspended from said supportingstructure and adapted to be disposed over a bed, each of said motorizedunits including a reversible electric motor and a drum connected to androtatably driven by the motor, a sling suspended from said drums andhaving end portions wound thereon and an intermediate portion adapted toengage under the body of a person occupying the bed, and a manuallyactuated control unit electrically connected to the motors forselectively energizing the motors and for causing the motors to beselectively driven in either direction for winding the sling ends onsaid drums or for unwinding the sling ends therefrom for raising,lowering or turning the bed patient.

2. An apparatus as in claim 1, means slidably and rotatably mountingsaid motor units on said structure,

said means providing a gimbals action between the supunits.

3. An apparatus as in claim 1, and means for automatically interruptingthe electric current to said motors when the sling ends are wound on orunwound from said drums to a predetermined extent.

4. An apparatus as in claim 1, said control unit including a buttonelectrically connected toy and controlling each of said motors, meansmounting said buttons for vertical sliding movement for regulating thespeeds at which the motors are selectively driven, and means mountingsaid buttons for rocking movement in opposite directions for causingsaid motors to be driven either clockwise or counterclockwise.

5. An apparatus as in claim 1, said sling comprising non-elasticflexible tapes Wound on and depending from said drums, a bridlesuspended from each tape, and a drawsheet constituting the bottomportion of the sling and having end portions connected to said bridles.

6. An apparatus as in claim 5, each of said bridles including a rolleron which one of the end portions of the drawsheet is wound andfrictionally anchored, and pawl and ratchet means associated with thebridle and the roller thereof permitting the roller to be turned freelyin a direction for winding the drawsheet end thereon and releasable forpermitting the drawsheet to be unwound therefrom.

7. An apparatus as in claim 1, said supporting structure comprising anarch-shaped frame adapted to straddle the bed and having a top portionfrom which said motorized units are suspended, and caster wheels providing a mobile support for said frame.

8. An apparatus as in claim 7, said frame having extensible upright sideportions for varying the elevation of the top portion relative to thebed.

References Cited UNITED STATES PATENTS 1,487,150 3/1924 Deakins 584 X2,959,791 11/1960 Ramsey 588.X 3,401,410 9/1968 Welborn et al 561 CASMIRA. NUNBERG, Primary Examiner US. 'Cl. X.R. 5-61, 86

